Abstract: A method for forming a polycrystalline semiconductor thin film according to the present invention includes the steps of: forming a semiconductor thin film partially containing microcrystals serving as crystal nuclei for polycrystallization on an insulating substrate; and polycrystallizing the semiconductor thin film by laser annealing.

Abstract: A laser annealing method for a semiconductor thin film for irradiating the semiconductor thin film with a laser beam having a section whose outline includes a straight-line portion, so as to change the crystallinity of the semiconductor thin film is provided, wherein the semiconductor thin film is overlap-irradiated with the laser beam while the laser beam is shifted in a direction different from a direction along the straight-line portion. A thin film semiconductor device fabricated by use of the laser annealing method is also provided.

Abstract: A thin film on a substrate is patterned so as to include an area in which a thin film transistor is to be formed and an area of another patterned thin film or a semiconductor device, and so as to have a size larger than the total size of the areas. Next, the patterned thin film is annealed. After the annealing, a part of the inside area of the patterned thin film is patterned. The part of the thin film is used for forming a thin film transistor.

Abstract: The present invention relates to a thinfilm transistor array designed to drive an active-matrix type liquid-crystal panel to be incorporated in a liquid-crystal display device, and is to offer a thinfilm transistor array solving the conventional problems of disconnections possible between the display electrodes and the drain electrodes and short-circuits possible between the display electrodes and the data wiring. By these, high-quality images can be displayed with a high reliability can be obtained together with an improved fabrication process thereof. In order to accomplish these objectives of the invention, the display electrodes of said thinfilm transistor array are disposed between the gate insulation layer and the inter-insulation layer, and the display electrodes are connected to the drain electrodes by means of a data wiring disposed through contact holes provided through the inter-insulation layer.